Blade for rotary pumps



Jan. 16, 1934. B, M STALEY 1,943,561

BLADE FOR ROTARY PUMPS Filed July 6, 1932 WITNESSES 4 lNVENTb Patented Jan. 16, 1934 UNITED" STATES PATENT oFFIcE 4 Claims. (Cl. 103-136) This invention relates to pumps and com- 'pressors of the rotary type in which radially movable vanes or blades are utilized in the rotors thereof, and pertains-more particularly to'the productionof blades for such use having a pump wall-engagingend formed of one ltind of material and a body portion formed of another.

An object of the invention is to provide blades of this characterhaving greatly improved wearing qualities and forproducing them in a much more economical manner than has been heretofore done.

A more particular object is to provide an improved method for makingthese blades with an outeror pump Wall-engaifng end formed of a sturdy high wear-resistin non-metallic material such as hard rubber, od; fibrous material impregnated with resinous compounds or the like, and a' body portion formed of a suitable 'metal adapted to give them rigidity andsuflicient Weight to insure their responding to the centrifugal action of the rotor in the manner necessary for their proper operation. These and various other objects, as well 'as the various other novel features and advantages of the invention, will be apparent when the following detailed description isread in conjunction with the accompanying drawing, of which Fig. 1- is a fragmentary sectional view taken through a portion of the rotor and the pump wall of a rotary pumpemploying blades constructed in accordance with the invention; Fig. 2 a perspective view of one embodiment of the invention showing. the interengaging parts of the pumpzwall-engaging end and body portion proper of the blade; Fig. 3 a view similar to Fig. 2 of another embodiment of the invention; Fig. 4 a perspective view of the pump wall-engaging end or tip of theblade shown in Fig. 2; afid Fig. 5 a similar view of the tip of the blade shown in Fig. 3.

I am well acquainted with the fact that blades or vanes of the character contemplated .by this invention have been made in the past for use in pumps where fluids are encountered which have a'tendency-torapidly destroy blades made wholly of metal. However, as heretofore made the life of such blades has been relatively 50. short because of various structural weakness,

vand their manufacture has been relatively costly. In accordance with the prior practice, both parts of the'blade are machined to shape and thenfittedtogether, both of which operations add. to their cost. Furthermore, it has to fail prematurely.

been found that the vibration andlateral forces to which such blades are subjected in service have a tendency -to loosen. these older blade parts quite rapidly, which in turn causes them v This invention is predicated upon mydiscovery that blades of this character, having considerably improved quality over the older kinds of blades, can be produced at a much lower cost than was heretofore possible by die-casting the 5" body portion of the blade onto the tip or pump wall-engaging end. In accordance with the invention the only-m'achiningor preforming. operation required upon the parts comprising the blade is that involved in the forming of the tip. This is done by forming it to a desired outer shape in any-suitable fashion and providing an undercut tongue on its inner end 'for attaching the .body portion to it. The body which may be formed; of any suitable metal having the necessary qualities, as set forth above, is die-cast upon the undercut tongue provided on the tip for suph purpose, the casting operation being carried out under relatively high pressures and comparatively low tempera- 30' tures so that the heat required in the operation will not besufficient to injure the non-metallic 1 tips when the. cast is made.

By way of illustrating the invention, reference is had to the drawing, in Fig. 1 of which 35 the numeral 1 designates a portion of a rotary pump housing and 2'the rotor thereof in which a plurality of blades 3 embodying the invention is mounted in radially extending slotsj 1. In accordance with the invention, the first step in the making of theseblades is that of reducing a piece of material selected for the tip ends 5 to a desired shape, such for example as shown in Figs. 2, 3, 4 and 5, and then die-casting the body 6 thereon. This shaping of the tip may be accomplished in any suitable fashion as long as a suitable undercut tongue 7 or equivalent formation is provided on the body-engaging side formaking the necessary union with the body, and the die-casting may also be performed by various means as will be readily appreciated. j

One of the outstanding advantages of blades made in this way is their greaterstrength, which 1 tion of blades is that they have a tendency. particularly after they become somewhat worn, to

' wabble endwise in the slots of the rotors in which which is desirable.

they are mounted and as a result their body and tip portions are subjected to unequal lateral forcesv which in turn tend to separate them along the plane of their ,union. To augment this difliculty' I so develop the tongue '7 on the body-engaging ends that a portion of the body is disposed to engage the tongue in a manner to resist any relative lateral movement between the two parts. Referring to Figs. 2 and 4, as will be observed the tongue 7 formed on the bottom of the tip 5 is divided into two sections and these are separated from each other in ,the

middle, of the tip so that a portion -,of the body projects between the inner ends thereof and functions as an abutment or key holding the two parts of the blade rigidly against endwise relative movement. In the preferred form of blade, however, as shownin Figs. 3 and 5, in stead of providing a. divided tongue on the bottom of the tip 5a, it is all formed in one section,

but it is not extended completely acrossgthe tip, it being spaced inwardly from the edges of the tip wallproper. Thus, when the bladeis formed this tongue is embedded in a pocket whereby lateral separation or movement of the blade parts is not only prevented, but the contact line between the tip and body is perfectly smooth,

It will be readily-appreciated by those skilled in the art that, due to the simplicity of this method of making such blades, their cost\ of manufactureoyer' the old method of making them is considerably reduced. Also, that as a result of the much more rigid union provided between the parts they will have considerably greater strength and conseqliently longer life.

l the rotor slots with mode of operation of my invention, and have illustrated and described what I now-consider tobe its best embodiment. J-Iowever, I desire to have it understood that, ,within, the scope of the appended claims, the invention. may be with those of the tili' practiced otherwise thari as specifically illushated, and described. 2

Lclaim:

1. A rotary pumpblade comprising a bearing tip formed of high wear-resisting material provided on its outer end with a curved pumpwvallengaging surfaceand on its inner end with an undercut tongue of lesser length than the body of the tip, and a'metal body portion die-cast upon said tip with its.tip-engaging end-.rigidiy engaging said tongue in a manner; to prevent endwise movement of said tip with respect "to said body and its side walls extending in alignment with those of; the tip.

2. A rotary pump blade comprising, a bearing tip formed of high wear-resisting materialprovided with parallel side walls, a curved pumpwall-engaging surface and having'a centrally disposed undercut tongue on its-body-engaging' end of lesser length than its body and a metal body rigidly die-cast upon said tip with its adjacent end thereof. abutting against that of the tip end and its side walls extending in alignment 3. A rotary pump blade comprising a pumpwall-engaging end section of high wear-resisting material provided with parallel side walls, a

curved pump-wall-engaging outer end, a pair of spaced undercut tongues on its inner bodyengaging end, and a metal body section rigidly die-cast upon said tongues with its adjacent end abutting against that of the wall-engaging section and its sidewalls extending in alignment therewith.

4. A rotary pump blade comprising a pump wall engaging end,section of high wear-resisting Y material provided with parallel side walls, 'a

curved pump-wall-engaging outer end and an undercut tongue on its inner body-engaging end, said tongue being oflesser width and thickness than the width and thickness of the blade and of the wear end section rigidly die-cast upon said tongue with its adjacent end abutting against that of the wear end and its side wall located with its edges spaced from the side ,wall, edges of the blade, and, a metal body section having a cross sectional shape'the same as that extending in alignment with the side walls I thereof I BENJAMIN M. STALEY. 

